1. Field of the Invention
The present invention relates to a vessel propulsion apparatus.
2. Description of the Related Art
A known vessel propulsion apparatus includes an exhaust passage by which exhaust discharged from a combustion chamber is discharged underwater. The exhaust passage does not extend upward toward a downstream side but extends downward to an exhaust outlet that opens underwater. Thus, even if condensed water forms due to cooling of the exhaust inside the exhaust passage, the water flows downward inside the exhaust passage and moves away from the combustion chamber. Engine misfire due to entry of condensed water thus does not occur. Engine stall due to misfire thus does not occur with the conventional vessel propulsion apparatus.
Meanwhile, U.S. Pat. No. 7,867,048 B2 and U.S. Patent Application Publication No. 2010/0240269 A1 disclose a vessel propulsion apparatus that includes an exhaust passage by which exhaust discharged from a combustion chamber is discharged underwater and a condensed water passage connected to the exhaust passage. The exhaust passage includes an upward guiding portion that guides the exhaust upward. An upstream end of the condensed water passage is connected to a lower end portion of the upward guiding portion. Condensed water formed by cooling of the exhaust collects at the lower end portion of the upward guiding portion and is discharged into the condensed water passage. Entry of condensed water into the combustion chamber is thereby prevented.